Not sure how to soundproof your noisy water pump? Many users think it’s impossible to do it, so they suffer through the noise without having to. It’s in fact really easy to reduce the noise coming from a water pump by enclosing it in a soundproof box.

I’ve seen this work multiple times, especially when used for generators and water pumps. In this article I’ll share with you the exact steps for building a soundproof box for your water pump.

1. DIY Soundproof box for water pumps

1. Identify the type of noise

Before you start building the box, it’s important to know what type of noise your water pump produces. There are two different types:

Impact noise – also known as structure-born or vibration noise. As the name says, these are low frequency sound waves produced by vibrations. Other structures that surround the source of the noise may also vibrate, thus amplifying the noise further. This is why for some soundproofing projects you have to use hard and flexible impact-blocking material rather than classic foam panels.

Airborne noise – these are mid to high frequency sound waves transmitted only through air. So they don’t cause any vibrations on the surrounding structures and are easier to block.

In almost every case, a water pump will produce both impact and airborne noise. Older pumps and those of lesser quality produce more impact noise. When that’s the case, the best results are gained by surrounding the pump with impact-blockers, since they also block airborne noise to a high degree.

2. Get the material for the box

To make a soundproof box for a water pump you’ll need:

• wooden panels (MDF panels work best for soundproofing)
• nails or screws
• impact blocking material to cover the interior of the box

You can get wooden panels in places like Home Depot or Amazon. I recommend MDF panels because they’re properly dense and thick. MDF is the preferred material for subfloors as well, for that exact function – blocking impact noise.

There are dozens of professional impact blockers you can use to cover the interior of the box. My favorite for a long time has been Mass Loaded Vinyl (link to Amazon). Many products are in fact Mass Loaded Vinyl under a different name, with a little extra material like acoustic foam or an adhesive side that ramps up the price. I find those to be completely unnecessary. The real noise-blocking comes from the MLV itself, so I suggest using the original and saving money in the process.

3. Measure the water pump

Measure the water pump before buying the panels. You can order the exact size needed at Home Depot. Make sure that the box is slightly bigger than the water pump, but not too much.

The closer you can get to the source of the noise, the better.  But take into consideration when ordering the panels that you’ll cover the interior with a layer of soundproofing material. In case of MLV, that’s only 1/8 of an inch extra on all sides.

4. Make the necessary hole(s) in the panel(s)

Before assembling the box, make sure to cut any necessary holes for the pipe and for cooling with a cutting bit or a jigsaw blade. You don’t want to entirely cover the water pump, especially if gets heated up. Leave a few small holes for cooling. Keep the size of the hole for the pipe to a minimum to prevent additional sound from coming out.

5. Cover the panels with soundproofing material

With the panels ready, cut the Mass Loaded Vinyl to size for each panel. Use a regular sharp knife to do it.

Then use a spray adhesive like 3M Spray Adhesive to install Mass Loaded Vinyl on each panel. Alternatively, you can nail or screw it to the panel. It makes zero difference. If you use some other material that has a self-adhesive side, then simply stick it to the panels.

6. Assemble the box

Now comes the fun part. Use nails or screws to attach the panels together to create a box. Make sure to leave one side open so that you can actually place the water pump inside. If there are any gaps between the panels, use self-adhesive weatherstripping tape to seal it further.

7. Place soft and thick material under the water pump

To further reduce sound transmission made by the vibrations, place the water pump on a really thick rug or an anti-vibration pad. This is especially helpful if the pump is currently placed on a hard concrete floor or a hollow wooden floor.

8. Cover the water pump with your home-made soundproof box

If you followed the steps outlined above, you’ve built your very own soundproof box! You’ll see an immense reduction in noise as soon as you get the water pump inside.

If the noise is still too loud, add another layer of Vinyl on the inside, or attach more wooden panels to the box from the outside. You can do this immediately if you have any material left upon finishing the project.